diff options
Diffstat (limited to 'loginutils/vlock.c')
| -rw-r--r-- | loginutils/vlock.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/loginutils/vlock.c b/loginutils/vlock.c new file mode 100644 index 0000000..0262da5 --- /dev/null +++ b/loginutils/vlock.c @@ -0,0 +1,106 @@ +/* vi: set sw=4 ts=4: */ +/* + * vlock implementation for busybox + * + * Copyright (C) 2000 by spoon <spoon@ix.netcom.com> + * Written by spoon <spon@ix.netcom.com> + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ + +/* Shoutz to Michael K. Johnson <johnsonm@redhat.com>, author of the + * original vlock. I snagged a bunch of his code to write this + * minimalistic vlock. + */ +/* Fixed by Erik Andersen to do passwords the tinylogin way... + * It now works with md5, sha1, etc passwords. */ + +#include <sys/vt.h> +#include "libbb.h" + +static void release_vt(int signo UNUSED_PARAM) +{ + /* If -a, param is 0, which means: + * "no, kernel, we don't allow console switch away from us!" */ + ioctl(STDIN_FILENO, VT_RELDISP, (unsigned long) !option_mask32); +} + +static void acquire_vt(int signo UNUSED_PARAM) +{ + /* ACK to kernel that switch to console is successful */ + ioctl(STDIN_FILENO, VT_RELDISP, VT_ACKACQ); +} + +int vlock_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int vlock_main(int argc UNUSED_PARAM, char **argv) +{ + struct vt_mode vtm; + struct termios term; + struct termios oterm; + struct vt_mode ovtm; + uid_t uid; + struct passwd *pw; +/* XXX: xgetpwuid */ + uid = getuid(); + pw = getpwuid(uid); + if (pw == NULL) + bb_error_msg_and_die("unknown uid %d", (int)uid); + + opt_complementary = "=0"; /* no params! */ + getopt32(argv, "a"); + + /* Ignore some signals so that we don't get killed by them */ + bb_signals(0 + + (1 << SIGTSTP) + + (1 << SIGTTIN) + + (1 << SIGTTOU) + + (1 << SIGHUP ) + + (1 << SIGCHLD) /* paranoia :) */ + + (1 << SIGQUIT) + + (1 << SIGINT ) + , SIG_IGN); + + /* We will use SIGUSRx for console switch control: */ + /* 1: set handlers */ + signal_SA_RESTART_empty_mask(SIGUSR1, release_vt); + signal_SA_RESTART_empty_mask(SIGUSR2, acquire_vt); + /* 2: unmask them */ + sig_unblock(SIGUSR1); + sig_unblock(SIGUSR2); + + /* Revert stdin/out to our controlling tty + * (or die if we have none) */ + xmove_fd(xopen(CURRENT_TTY, O_RDWR), STDIN_FILENO); + xdup2(STDIN_FILENO, STDOUT_FILENO); + + xioctl(STDIN_FILENO, VT_GETMODE, &vtm); + ovtm = vtm; + /* "console switches are controlled by us, not kernel!" */ + vtm.mode = VT_PROCESS; + vtm.relsig = SIGUSR1; + vtm.acqsig = SIGUSR2; + ioctl(STDIN_FILENO, VT_SETMODE, &vtm); + + tcgetattr(STDIN_FILENO, &oterm); + term = oterm; + term.c_iflag &= ~BRKINT; + term.c_iflag |= IGNBRK; + term.c_lflag &= ~ISIG; + term.c_lflag &= ~(ECHO | ECHOCTL); + tcsetattr_stdin_TCSANOW(&term); + + do { + printf("Virtual console%s locked by %s.\n", + option_mask32 /*o_lock_all*/ ? "s" : "", + pw->pw_name); + if (correct_password(pw)) { + break; + } + bb_do_delay(FAIL_DELAY); + puts("Password incorrect"); + } while (1); + + ioctl(STDIN_FILENO, VT_SETMODE, &ovtm); + tcsetattr_stdin_TCSANOW(&oterm); + fflush_stdout_and_exit(EXIT_SUCCESS); +} |